Oscar Pistorius, the 400m Paralympic sprinter dubbed "the fastest man on no legs", will tomorrow bid to prove that his prosthetic limbs do not give him an advantage. The South African remains determined he will be competing at this summer's Olympic Games in Beijing as he begins his appeal to the Court of Arbitration for Sport (CAS) in Lausanne.

"If the blades give an advantage," insisted Pistorius, "why are the other Paralympic athletes not running the times I am achieving?"

The Paralympic world record-holder at 100m, 200m and 400m refused to give in after the International Association of Athletics Federations ruled against him in January following their official study into the use of his prosthetic j-shaped legs.

The IAAF had sent Pistorius for a series of tests to Cologne with Gert-Peter Brueggemann, a bio-mechanics professor. His findings revealed that the prosthetic blade used 25% less energy than able-bodied runners at the same speed.

Since then, Pistorius, 21, has called in expert help from France and the USA and insisted he has evidence to show that he should be allowed to compete alongside able-bodied athletes.

He said: "I don't know what the motives are for the IAAF making the decisions they did, but ... things are going to unravel and I hope for a better outcome. There is a lot of discrimination against disabled people and I don't think all the variables were considered.

"I feel that it is my responsibility on behalf of myself and all other disabled athletes to stand firmly and not allow one organization to inhibit our ability to compete using the very tools without which we simply cannot walk, let alone run. I will not stand down.

"This case is important not just to me, but to all disabled persons who just ask for the chance to compete fairly on the sporting field with able-bodied athletes."

Pistorius made high-profile appearances in able-bodied 400m races last year, finishing second in Rome and then last - before being disqualified for running out of his lane - in Sheffield.

The CAS hearing is scheduled to last two days, and Pistorius is likely to know the outcome within a month. But even if he is allowed to compete in Beijing, then he will be faced with the tough problem of actually qualifying for the Games.

The Olympics in Beijing are only 101 days away and he stills needs to achieve a 400m qualifying time of 45.95 secs. His best, the Paralympic world record, is 46.56.

He knows he needs to find as many able-bodied races to help him improve his times.

Pistorius had his legs amputated below the knee when he was only 11 months old after being born with no fibula bones and in Athens four years ago, he won the 200m at the Paralympic Games.

He is also known as Blade Runner because of the shape of his prosthetics and his dream of competing at the Olympics took on a greater relevance in 2005 when, at the South African Championships, he finished sixth in an able-bodied 400m.